1. Field of the Invention
The present invention relates to a structure of an air cleaner for a scooter type vehicle using a power unit with an internal combustion engine and a power transmission device to the rear wheel integrated with each other.
2. Description of Background Art
For example, such an air cleaner is disclosed in the following JP Patent No. 4280361 (FIG. 5, FIG. 6) that in an air cleaner for a scooter type vehicle, placed above a power unit with an internal combustion engine and a power transmission device to the rear wheel integrated with each other, the air cleaner has a plurality of functions so that a blowby gas return pipe is connected for returning blowby gas from the internal combustion engine to the air cleaner, the blowby gas is sent together with intake air to the internal combustion engine so as to be burned, and an air opening pipe (“a vacuum conduit” in JP Patent No. 4280361 (FIG. 5, FIG. 6)) communicating with a carburetor is connected, and so on.
As disclosed in JP Patent No. 4280361 (FIG. 5, FIG. 6), if an air cleaner has a plurality of functions in a scooter type vehicle, the air cleaner is placed above a power unit which is vertically swingably supported on a vehicle-body frame. This produces constraints on space in the up-and-down directions in order to ensure the amount of Vertical swinging motion in addition to constraints on space above the power unit in the fore-and-aft directions. From the viewpoint of this, accordingly, further improvements are required.